LED lamp with uniform omnidirectional light intensity output

Abstract

A light emitting apparatus comprises: an LED-based light source; a spherical, spheroidal, or toroidal diffuser generating a Lambertian light intensity distribution output at any point on the diffuser surface responsive to illumination inside the diffuser; and a base including a base connector. The LED based light source, the diffuser, and the base are secured together as a unitary LED lamp installable in a lighting socket by connecting the base connector with the lighting socket. The diffuser is shaped and arranged respective to the LED based light source in the unitary LED lamp to conform with an isolux surface of the LED based light source. The base is operatively connected with the LED based light source in the unitary LED lamp to electrically power the LED based light source using electrical power received at the base connector.

The invention claimed is: 
     
       1. A light emitting apparatus comprising:
 an LED-based light source; 
 a phosphor containing toroidal diffuser generating a light intensity distribution output responsive to illumination inside the diffuser; 
 a base comprising a pedestal hosting said LED-based light source and a base connector; 
 said diffuser surrounding said LED-based light source; 
 the LED-based light source, the diffuser, and the base being secured together as a unitary LED lamp installable in a lighting socket by connecting the base connector with the lighting socket; and 
 the base being operatively connected with the LED-based light source in the unitary LED lamp to electrically power the LED-based light source using electrical power received at the base connector. 
 
     
     
       2. The light emitting apparatus of  claim 1  wherein said pedestal is generally cylindrical. 
     
     
       3. The light emitting apparatus of  claim 1  wherein said LED-based light source is received within an opening in said diffuser. 
     
     
       4. The light emitting apparatus of  claim 3  wherein said LED-based light source is arranged tangentially to said opening. 
     
     
       5. The light emitting apparatus of  claim 1 , wherein said base connector comprises an Edison base connector. 
     
     
       6. The light emitting apparatus of  claim 1 , wherein said toroidal diffuser has a circular cross-section. 
     
     
       7. The light emitting apparatus of  claim 6 , wherein said toroidal diffuser is a true torus. 
     
     
       8. The light emitting apparatus of  claim 1 , wherein said toroidal diffuser is one of prolate and oblate circular in cross-section. 
     
     
       9. The light emitting apparatus of  claim 1 , wherein said LED-based light source comprises a plurality of LEDs mounted to a planar circuit board. 
     
     
       10. The light emitting apparatus of  claim 1 , further including heat dissipating fins. 
     
     
       11. The light emitting apparatus of  claim 1 , wherein said base houses electronics for energizing the LED-based light source. 
     
     
       12. The light emitting apparatus of  claim 1 , further comprising a fan. 
     
     
       13. The light emitting apparatus of  claim 1 , wherein said toroidal diffuser is multi-sided and includes rounded transitions between adjoining sides. 
     
     
       14. The light emitting apparatus of  claim 1 , wherein said base further includes a metal slug. 
     
     
       15. The light emitting apparatus of  claim 1 , wherein said toroidal diffuser extends outwardly from said base in a plane transverse to the axis of the pedestal. 
     
     
       16. The light emitting apparatus of  claim 1 , wherein said toroidal diffuser is comprised of plastic. 
     
     
       17. The light emitting apparatus of  claim 9 , wherein said toroidal diffuser includes an opening sized to mate with the planar circuit board.